textproduct: Albany

WHAT HAS CHANGED

Chances for severe thunderstorms and flash flooding will decrease by later this afternoon, as a cold front pushes east across the region. Added patchy fog late tonight once winds diminish. Lowered chances for any showers on Wednesday.

KEY MESSAGES

1) There is a Marginal (level 1 of 4) to Slight (level 2 of 4) for excessive rainfall leading to isolated flash flooding this afternoon south/east of Albany. There is also a Marginal Risk (level 1 of 5) for severe thunderstorms across far eastern New York into western New England.

2) Another system brings the next chance for showers and thunderstorms Thursday into Friday. Some stronger storms may occur, along with locally heavy rainfall.

DISCUSSION

KEY MESSAGE 1...

Cold front moving east across far eastern NY into western New England through the rest of the afternoon. A low-topped line of convection developed along and just east of the front. Gusty winds of mainly 40-50 mph are expected, although a few damaging wind gusts cannot be ruled out due to strong wind shear. There is a low probability (2-4%) of a brief/isolated tornado mainly in the N. Berkshires into S. Vermont where effective helicity of highest. Otherwise, widely scattered flash flooding may occur where there is any training especially across areas that received heavy rainfall early this morning such as in Dutchess/Litchfield Counties. The threat for any severe/flash flooding will quickly end by later this afternoon around 4 pm as the cold front moves east out of our area.

It will turn breezy and less humid behind the cold front, with westerly winds gusting 20-30 mph into the evening. Winds will subside later tonight, with patchy fog developing late.

KEY MESSAGE 2...

More tranquil weather is expected for Tue and also Wed, with high pressure in place. Humidity levels will be more comfortable compared to today. Model guidance is indicating a very small/compact low moving onshore near SE New England, but latest trends are for this system to remain south/east of our area.

By Thu, moisture and humidity will increase again as a persistent south-southwest flow develops around the periphery of a Bermuda high. Dewpoints are expected to rise into the 70s, with PWAT anomalies increasing to +1 to +2 STDEV. There does appear to be a lack of synoptic scale forcing through Thu morning, as a frontal system is expected to be positioned north/west of Lake Ontario with no significant push to the south due to the strengthening Bermuda high. Eventually the front should slowly drift south/east into our area later Thu into Fri, which is when chances for showers/T-storms increase. Due to uncertainty in coverage/timing, there is low confidence in severe storm and/or flash flood potential. AI NWP convective hazards forecast shows at least some potential for severe storms during this time. Also, with such a humid/moist environment and wet antecedent ground conditions, there will likely be a threat of at least isolated flash flooding.

AVIATION /18Z MONDAY THROUGH SATURDAY/

A cold front has moved through KGFL and KALB this afternoon transitioning the winds to the west and bringing breezy conditions through 04/00z with gusts ranging between 20 and 28 knots. After 04/00z, winds decrease and become less than 15 knots through 06z when they become calm for the overnight hours tonight. For KPSF and KPOU, the cold front is on the way and arriving between now and 20z with rain showers ahead of the front. Brief IFR conditions exist in these rain showers mentioned in a TEMPO group for KPSF through 20z when the front should be moved through. Then winds increase and shift to the west through 04/00z. For all TAF sites, patchy fog could develop between 04/09z and 04/12z as skies clear tonight, calm winds, and recent rainfall makes conditions favorable for patchy fog to develop. Brief IFR/LIFR conditions could occur during this timeframe and has been introduced in TEMPO groups. After 04/12z, VFR conditions return and continue through the end of the TAF period.

Outlook...

Tuesday Night: No Operational Impact. Patchy FG. Wednesday: No Operational Impact. NO SIG WX. Wednesday Night: Moderate Operational Impact. Slight Chance of SHRA. Thursday: High Operational Impact. Definite SHRA...TSRA. Thursday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Friday: High Operational Impact. Likely SHRA...TSRA. Friday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Saturday: Moderate Operational Impact. Chance of SHRA...TSRA.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. MA...None. VT...None.